ZERO DISCHARGE Opportunities and Challenges

1
ZERO DISCHARGE Opportunities and Challenges

• Presented by Mr. Stig Svalheim
• FORCE Seminar
• Stavanger, 22nd April 2004

2
Overview

• NPD-focus Balance the need to reduce discharges
  with possible impacts on reserves, safety and
  costs
• Background and status implementation
• Environmental Impact Factor (EIF)
• Produced water trends and zero discharge measures
• Challenges and way forward
• Conclusions

3
The Zero Discharge Policy

• Defined by the Parliament in accordance with the
  precautionary principle
• Applies already for new stand-alone developments
  and by the end of 2005 for existing installations
• Policy covers production, drilling and pipelines
• Stricter interpretation will be applied for the
  vulnerable Lofoten and Barents sea areas.

4
International obligations (OSPAR)

• Current requirement max 40 mg/l OiW
• New agreed recommendation
• Max 30 mg/l OiW
• 15 total oil discharge reduction from 2000 to
  2006
• Targets within reach if the operators zero
  discharge plans are implemented, but a challenge
  beyond 2006 as water production increases (ref.
  SFT)

5
The Zero Discharge Target - North Sea and
Norwegian Sea areas

• No discharges of hazardous chemicals (SFTs black
  and red categories)
• No discharges or minimising discharges of
  naturally-occurring environmental toxins
• No or minimised discharges of substances which
  could lead to environmental harm
• Oil (dispersed and dissolved)
• Chemicals in the SFTs yellow and green
  categories
• Other substances which could lead to
  environmental harm (e.g. drill cutting)
• Exception Crucial safety or technical reasons

6
Status Implementation

• 1996 Zero Discharge Goal launched
• 1998 Zero Discharge Work Group formed
• 2000 Mandatory operator strategy reporting
• 2003 Mandatory status reporting on progress and
  plans to reach the 2005-target
• SFT-feedback, Dec 2003
• In general, pleased with the operators progress
  and plans (80 reduction of environmental
  harmful substances on most fields)
• Total reduction of 42 of PAH and alkyl-phenol
  from 2000-2006
• Continuing challenge beyond the 2005 milestone as
  water production is predicted to increase
• Updated status reporting and committing plans
  during 2004

7
EIF a new tool for setting priorities

• EIF calculates the risk of environmental harm
  from produced water (PW) discharges on a field
• Modelling includes composition and quantity of PW
  and how the discharge disperses in the sea
• Management tool applied by both operators and
  authorities development spearheaded by Statoil

8
Source Statoil
9
Produced Water Trend on the NCS
Source RNB2004
10
Produced Water Management
Reuse
Reduction
Deposit
Treatment

• - Water shut-off
• - Downhole separation
• - Subsea separation
• - Smart wells etc.

• - PWRI for pressure maintenance

• - Produced water injection in deposit reservoir

• - C-Tour
• - EPCON
• - MPPE
• - Improved deoiling separation
• - Other methods

11
Already Implemented Measures

• Chemical substitution
• PWRI
• Brage (Norsk Hydro)
• Balder (ExxonMobil)
• Frigg (Total)
• Glitne (Statoil)
• Grane (Norsk Hydro)
• Heidrun (Statoil)
• Heimdal (Norsk Hydro)
• Jotun (ExxonMobil)
• Oseberg East (Norsk Hydro)
• Oseberg South (Norsk Hydro)
• Ringhorne (ExxonMobil)
• Snorre B (Norsk Hydro)
• Statfjord C (Statoil)
• Ula (BP)
• Valhall (BP)
• Visund (Statoil)

?
12
EIF-Trends on Major Fields
13
Each bar represent one specific measure on a
platform
14
Challenges

• Analysis based on the operators status reports
  uncertainty in reporting of costs and effects
• Key decisions not yet approved in the licenses
• Field specific solutions requires sufficient time
  for evaluations and testing
• Several new technologies and techniques to be
  installed how will they work in the long run?
• Low focus on methods to reduce water production
  in the operators status reports
• Long-term risk of reduced injectivity and/or
  reservoir souring from PWRI

15
PWRI and Risk of Bacteria Growth

• PWRI adds nutrients and sulphate from earlier
  sea water injection ? increased population of
  sulphate reducing bacteria possible
• Reservoir souring (H2S)
• Reduced injectivity
• Corrosion
• Workforce health risk
• ? Potential challenge for the entire upstream
  value chain (HSE - Resource Management)

16
Conclusions

• Avoiding potential harmful discharges to sea to
  operate sustainable and gain acceptance to
  operate
• Technologies are developed to meet the zero
  discharge goal, but cost-effective investment
  decisions need to be made
• Focus on minimising/avoiding the water production
  should not be forgotten!